Danish is written using the Latin alphabet, with three additional letters: æ, ø, and å, which come at the end of the Danish alphabet, in that order. A spelling reform in 1948 introduced the letter å, already in use in Norwegian and Swedish, into the Danish alphabet to replace the letter aa; the old usage still occurs in some personal and geographical names and old documents (for example, the name of the city of Ålborg is often spelled Aalborg). Aa is treated just like å in alphabetical sorting, even though it looks like two letters.

The same spelling reform changed the spelling of a few common words, such as vilde, kunde and skulde, to their current forms of ville, kunne and skulle, and did away with the practice of capitalising all nouns, which German still does. Modern Danish and Norwegian use the same alphabet, though spelling differs somewhat.